Printing machines using doctor blades in the inking systems usually have a plurality of adjustment pins or bolts which are coupled to the doctor blade so that the adjustment pressure of various regions of the doctor blade--which extends over the width of the inking cylinder--can be properly controlled. Some such apparatus use positioning motors to permit remote control of the individual adjustment pins or bolts of the doctor blade. The motors and the associated drive gears require service and maintenance from time to time.
It has been proposed to secure the motors on a cover of a housing or frame--see German Utility Model DE-GM No. 77 30 668. The motors and the associated apparatus becomes accessible for maintenance after removal of the cover plate. Thus, service of the motors and/or associated gearing and positioning apparatus can be effected easily after removal of the cover plate. Difficulties arise if additional structural elements are to be associated with the motors and/or the doctor blade positioning pins, respectively. Such additional apparatus may, for example, be remote indicating devices to indicate the particular position of the doctor blade, sensors or transducers for self-adjusting servo motors to provide positioning feedback and the like. The space available on the holding plate then becomes insufficient. Lateral extension of the holding plate or of chambers within the holding plate where the motors are located is not a proper solution since, then the distance between doctor blade adjustment pins must be increased beyond a proper limit. Accurate adjustment of the doctor blade with all circumferential areas of the associated printing cylinder may become impaired. The holding plate itself cannot be increased since, then, the overall printing machine must be built to be larger.
It has been proposed to utilize both sides of the holder plates to place constructional elements thereon. Access to the elements located at the inner portion of the housing, then, requires however that the elements at the outer side of the housing also be removed or specially protected. The holder plates, consisting of heavy pieces of metal, are heavy and of substantial size--extending across the width of the machine--and removal of the holder plate to obtain access to the interior of the inking mechanism for service of motors, gearing, or the like, introduces a hazard; after removal of holding bolts for the plates, the heavy plate may drop, causing damage to elements secured thereto and, additionally, resulting in a condition hazardous to personnel.